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Anyone know of a persulfate-free method to dye brown hair blonde? Answered

I'm allergic to persulfates, which are the chemicals in hair dye that strip the hair of its natural color.  I found this out after I had my hair professionally dyed, broke out, and went to the dermatologist.  I know that peroxide can also lighten hair, but I was hoping someone had good techniques or experiences with that or a similar persulfate-free lightening method.  My hair is very short so I'm not worried about breakage.  Normally I would just let something like this go, but as it turns out, I look really good as a blonde ;)


Yes and No. Hydrogen peroxide and the various (sodium, potassium, ammonium) persulfates work exactly the same way, by releasing free oxygen, thus oxidising the melanin in your hair into a colorless form. The only difference is that persulfates are stronger oxidisers that hydrogen peroxide. Peroxide, if the concentration is high enough and the processing time long enough, will bleach hair all the way to white. It takes less time using bleaches that also contain persulfates, that's all.

The peroxide ion has an oxidising potential of 1.77V, and the persulfate ion has an oxidising potential of 2.12V. Now, in some reaction, persulfate can be converted to the higher potential sulfate, and peroxide to hydroxyl, which is even more powerful than sulfate, and some commercial products may take advantage of these reactions. Persulfates can also, under some circumstances in an acidic environment, even produce hydrogen peroxide. As you can see, haircolor chemistry can be complicated, and this is only bleaching, let alone dye chemistry.

As for 3% peroxide, I've let my hair soak for 10 hours in 3% hydrogen peroxide solution, with little to no change in the color of my hair, perhaps a lightening of the cuticle, so be wary of anyone who tells you that you can lighten your hair appreciably simply by spraying it with 3% peroxide solution.

Bleaching the hair requires an alkaline environment, usually provided by ammonia (ammonium hydroxide), and hydrogen peroxide will not penetrate much into hair in the absence of an alkaline environment. Other chemicals used to create the necessary alkaline environment are ethanolamine and carbonates, like sodium carbonate or ammonium carbonate. An alkaline environment causes the cuticle of the hair (the outer layer) to swell and open like a porcupine, allowing the oxidising agent to enter the interior of the hair, where most of the melanin pigment is located. Also, hydrogen peroxide is a weak acid, and the alkaline environment will cause it to decompose into water and free oxygen more quickly.

In cosmetology terms, 3% hydrogen peroxide would be equivalent to a "10 volume" concentration, meaning it releases 10 times its volume in free oxygen, a fairly weak solution. Commercial haircolor products may contain as much as 12% hydrogen peroxide, or a "40 volume" concentration, which is used for powerful bleaching action.

As with all bleaching solutions, no matter if they use persulfates or not, the more concentrated the chemical and the longer you use it, the more damaging to your hair.

Spend too much time in a chlorinated swimming pool?

pro hairdresser - If you make a mess of it you have to live with the results. :-(

A 3% solution of hydrogen peroxide sprayed on your hair and left for 30 to 40 minutes will lighten your hair.  Rinse the solution out of your hair with cool water when you are happy with the color. You'll probably want to apply a good conditioner after you've rinsed your hair. A mild solution applied over a few days will give you a better result that using a strong solution in one dose.

I've heard that lemon juice and sunlight is good for lightening naturally blonde hair.